Automatic stirrer



Jan. 14, 1969. 5 PANKOW 3,421,743

AUTOMATIC STIRRER Sheet of 2 Filed June 23. 1967 v E. G7 PANKOW AUTOMATIC STIRRER Jan. 14, 1969 Sheet Filed June 25, 1967 United States Patent 3,421,743 AUTOMATIC STIRRER Edmund G. Pankow, Mansfield, Ohio, assignor to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed June 23, 1967, Ser. No. 648,286

US. Cl. 259-114 6 Claims Int. Cl. B01f 7/16 ABSTRACT OF THE DISCLOSURE A wire form stirrer structure adapted for automatic rotation within a cooked vessel. The wire form is supported on a hub member by a post which is carried by the hub member at a point remote from its axis of rotation for producing oscillatory as well as rotational movement of the wire form in response to rotation of the hub member.

Background of the invention This invention relates, in general, to automatic stirring apparatus and, more particularly, to agitator structure for use therewith.

Automatic stirrers comprising a rotatable hub and an integral agitator supported concentrically with respect thereto have, heretofore, been utilized for the purpose of mixing liquids as well as other substances. A magnet or other coupling means adapted to be rotated by a suitable motor is supported beneath a non-magnetic container or vessel in which the foregoing agitator is supported for rotation. When the consistency of the substance being mixed remains constant, the above-described arrangement works quite well, however, it is not totally satisfactory when the substance reaches a certain viscosity.

The operation of the foregoing stirring structure has been improved by providing a hub member having a pivot member disposed thereon at a point remote or offset from the center of rotation of the hub member. The agitator is mounted on the hub for rotation therewith by intercom necting means which frictionally engages the pivot member such that the agitator is capable of rotating with and/ or oscillating relative thereto.

Heretofore, the interconnecting means consisted of structure separate from the hub and agitator and was so constructed as to render difiicult the assembly and cleaning of the agitator and the hub as well as adding to the overall cost of the stirrer without proportionate benefit.

Objects Accordingly, it is the general object of this invention to provide new and improved stirring apparatus.

It is a more particular object of this invention to provide a new and improved agitator structure.

Another object of this invention is to provide new and improved means for interconnecting the components of a stirring device, which means permits relative motion between the components or simultaneous movement.

Summary Briefly, the present invention accomplishes the abovecited objects by providing a hub member adapted for rotation within a cooking vessel. The hub member carries on the upper surface thereof a pivot in the form of a post member which is disposed at a point remote from the axis of rotation of the hub. Agitator structure fabricated from a single piece of wire form is bent into a lurality of segments two of which cooperate to form an elongated recess comprising a bight portion and an enlarged area. The post member is received in the recess and is frictionally engaged in the enlarged area by the segments forming the recess.

3,421,743 Patented Jan. 14, 1969 Further objects and advantages of the present invention will become more apparent when considered in view of the following detailed description and drawings forming a part hereof.

Description of the drawings FIGURE 1 is a perspective view of an agitator structure incorporated in the invention;

FIG. 2 is a side elevational view of apparatus incorporating the invention;

FIG. 3 is a top plan view representing one mode of operation of the invention;

FIG. 4 is an enlarged fragmentary top plan view of stirring apparatus representing the invention; and

FIG. 5 is a view similar to FIG. 4, but with the components of the apparatus in different relative positions.

Description of the preferred embodiment Referring now to the drawings, especially FIGS. 1 and 2, reference character 10 designates generally agitator structure adapted to be supported for movement with a hub member 11. The agitator or arm structure 10, preferably made from any suitable material, for example, a single piece of steel wire, is bent or otherwise suitably shaped to form a continuous segmented structure suitable for mixing the contents of a vessel or container 12.

In the form of the invention illustrated, the hub member 11 comprises a permanent magnet covered with suitable material, for example, nylon. A permanent magnet 13 secured to a shaft 14 of a motor 16 (shown schematica'lly in FIG. 2) is adapted to be supported sub-adjacent the contain-er 12 directly below the hub member 11. The proximity of the two magnets provides a magnetic coupling therebetween serving to produce rotation of the hub member 11 with the magnet 13 when the latter is rotated by the motor 16 through the shaft 14. The container 12, made from any non-magnetic material, for example, aluminum, is supported on an electric heater structure 17 comprising a plurality of conventional coils 18. Thus, it can be seen that automatic stirring while cooking can be accomplished.

The arm structure 10, which is adapted to rotate in the same or counterclockwise direction with the hub member 11 in a manner to be described hereinafter, comprises a pair of similarly shaped arms 19 (best illustrated in FIG. 1), each having a substantially vertical leading segment 22 and an offset trailing segment 23 joined by a horizontally disposed spiral segment 24. Each of the offset segments 23 comprises a vertical component 26 and a horizontal component 27.

The components 27 are interconnected by a pair of resilient segments 28 forming a spring-like clip 25 delineating an elongated recess 29. The segments 28 are deformed or curved as indicated at 30 to form an enlarged area at 31 for receiving a ost or pivot member 32 in a manner to be described hereinafter. A bight portion 34 formed by the segments 28 is of sufiicient radius so as to permit insertion of ones finger to facilitate engaging and disengaging of the agitator 10 on the hub member 11.

Substantially V-shaped handle means 36 including a grip member 37 joins the arms 19 at the upper portion of the vertical leading segments 22 and together with segments 22, 23, 24, 27 and 28 form an integral or unitary agitator 10.

The post member 32 is secured to a top surface or wall 38 of the hub member 11 with its longitudinal axis disposed parallel to but remote from the axis of rotation of the hub member. The post member 32 comprises a tenon portion 39 (see FIG. 2) adjacent its lower extremity and a substantially cone-shaped top 40. A necked-down portion 41 of the post member which is disposed intermediate the tenon 39 and the head 40 is insertable into the enlarged area 31 through the open end of the recess 29. The

segments 28 are resilient and the space therebetween at the area 31, in the unstressed condition, is less than the diameter of the necked-down portion 41, accordingly, when the post member 32 is inserted the segments 28 are stressed. It will, therefore, be appreciated that the restoring force in the segments 28 causes them to frictionally engage the necked-down portion 41 thereby coupling the agitator 10, to the hub member 11 for rotation therewith. It will further be appreciated that as the viscosity of the contents of the vessel 12 increase due to application of heat, a resistance to rotation of the arm structure 10 is developed thereby causing relative slippage between the segments 28 and the necked-down portion 41. At this point the hub continues to rotate and due to the position of pivot member 32 relative to the axis of rotation of the hub member 11, oscillator motion toward and away from the center of rotation of the hub member 11, as shown in FIGS. 3, 4 and 5, is imparted to the agitator 10. The path of movement will be apparent by noting the successive positions occupied by the spiral-shaped segment 24. Starting with the solid line position, the spiral segment 24 moves to the position indicated at A, then B and then C. Two extreme positions of the agitator are more clearly illustrated in FIGS. 4 and 5 With the former corresponding to the solid line position and the latter corresponding to dotted line position indicated at B in FIG. 3.

As can be seen from FIGS. 2, 3, 4 and 5, the hub member 11 is provided with a plurality of fins 42 extending substantially radially from an annular Wall 43 thereof.

As can further be seen from FIG. 3, the fins 43, when the arms 19 move from the dotted line position A to the dotted line position C, the fins 43 pass closer to one or the other of the ofiset trailing members 23. It will be understood that as the fins are rotated they create a turbulence in the liquid, the resulting force of which impinges on the vertical and horizontal segments 26 and 27, particularly the former, thereby tending to rotate the arms 19 in the direction indicated by the arrows shown in FIG. 3. Consequently, it is possible to have simultaneous rotation and oscillation of the arms 19.

As can be seen in FIG. 2, the hub 11 is provided with a somewhat rounded bottom surface 44 which permits the agitator structure 10 to rock slightly thereby enhancing its stirring capabilities.

Since numerous changes may be made in the above described apparatus and different embodiments of the invention may be made without departing from the spirit thereof, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention: 1. In combination, stirring means for agitating the contents of a vessel, means for supporting said stirring means in said vessel, said means being adapted for rotation in said vessel,

said stirring means comprising a continuous segmented structure including a recess formed by cooperating segments thereof,

means carried by said support means and insertable in said recess for operatively interconnecting said stirring means and said support means,

said segments cooperating to form a spring clip structure defining said recess,

said recess forming segments delineating an enlarged area and a bight area, said means carried by said support being received in said enlarged area,

said bight area being of suflicient size for insertion of a finger therein for facilitating the interconnecting and disconnecting of said stirring means and said support means. 2. In combination, stirring means for agitating the contents of a vessel, means for supporting said stirring means in said vessel, said means being adapted for rotation in said vessel,

said stirring means comprising a continuous segmented structure including a recess formed by cooperating segments thereof,

means carried by said support means and insertable in said recess for operatively interconnecting said stirring means and said support means, :id enlarged area forming segments exerting suflicient frictional force on said means carried by said support means whereby said stirring means rotates in response to rotation of said support means when the viscosity of the contents of said vessel is relatively low, said force being of a magnitude to permit relative slippage between said segments and said means carried by said support means when the viscosity of said contents is relatively high. 3. In combination, stirring means for agitating the contents of a vessel, means for supporting said stirring means in said vessel, said means being adapted for rotation in said vessel,

said stirring means comprising a continuous segmented structure including a recess formed by cooperating segments thereof,

means carried b said support means and insertable in said recess for operatively interconnecting said stirring means and said support means,

said means carried by said support means being positioned at a point remote from the center of rotation of said support means and said segments and said means received in said recess being adapted for intermittent relative rotation and simultaneous movement, whereby oscillatory motion is imparted to said stirring means when there is relative rotation between said segments and said means carried by said support means.

4. Structure as specified in claim 3, wherein said segments cooperate to form a spring-like clip defining said recess.

5. Structure as specified in claim 4, wherein said recess defining segments delineate an enlarged area and a bight area, said means carried by said support being received in said enlarged area.

6. Structure as specified in claim 5, wherein said bight area is of sufficient size for insertion of a finger for facilitating insertion of said means carried by said support means into said recess.

References Cited UNITED STATES PATENTS ROBERT W. JENKINS, Primary Examiner.

US. Cl. X.R. 259-444 

